Much of London-based American composer Arlene Sierra’s music is inspired by the natural world and its complex, often miraculous processes. As an artist, Sierra is especially sensitive to how human (read: non-natural) systems routinely conspire to challenge and disrupt the elegant, ancient rules of life that predate us. A quick glance at her catalog reveals several examples of this focus, with titles like Nature Symphony, Bird Symphony, Birds and Insects, Urban Birds, Insects in Amber, and Avian Mirrors. Butterflies Remember a Mountain is Sierra’s second piano trio. She writes that it “was inspired by a study of Monarch butterfly migration patterns…” Sierra took the incredibly evocative title of this 2013 work from a scientific article written during that same year. It details how migrating monarchs make a phantom left turn around the long extinct mountain that likely once stood over part of present-day Lake Superior. The world changes around them over countless millennia, but they do not forget. It’s beautiful to think of such deep, geologic time living on in these delicate but impossibly tough little creatures, and Sierra’s poetic tribute echoes the article’s closing statement about how, in this case at least, “flesh outlasted stone.”